1. Field of the Invention
The present invention relates to a novel interposer for use in the assembly of electronic modules which accommodates the camber on the electronic components while providing improved interconnection.
2. Description of Related Art
In the manufacture and assembly of electronic modules, deformities on the substrate surface make interconnection difficult. Typical ceramic substrates exhibit about 25 to about 50 .mu.m camber as measured from a flat surface of the substrate. When a device with conventional solder ball interconnections is joined to such a substrate, some of the solder balls will not contact the melting pads leading to opens in the circuitry of the module.
One prior art method of providing better interconnection between the device and substrate is through z-axis films (ZAFs). ZAFs are typically anisotropic electrically conductive adhesive films consisting of thousands of conductive particles dispersed throughout the adhesive film. Contact between the conductive particles when compressing the ZAF provide the electrical pathway.
However, as the demands for miniaturization continues, spacing between particles and the precision in spacing between particles becomes increasingly important. Too many particles may lead to shorts while too few particles may not provide an adequate conductive pathway. Prior art techniques of providing conductive particles in an array that will insure particles at every contact pad of the devices is time consuming and therefore costly.
Bearing in mind the problems and deficiencies of the prior art, it is therefore an object of the present invention to provide an apparatus for providing electrical interconnection between electronic components which does not require precise alignment of the interconnections with the contact pads and compensates for substrate camber.
It is another object of the present invention to provide a method and apparatus for assembling an electronic module having improved interconnections.
A further object of the invention is to provide an electronic module which has a substantial reduction in opens between interconnections caused by camber.
Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.